Are linen sheets safer than cotton sheets?
Linen and cotton are both good choices when they are untreated. Finishes matter more than the plant fiber.
What is in it
Linen comes from flax. Cotton comes from the cotton plant. Both are breathable plant fibers. The bigger concern is the finish added after weaving.
Watch for labels like wrinkle-resistant, no-iron, easy-care, or stain-resistant. Those can point to resin or repellency treatments, depending on the product.
What the science says
A 2025 Reviews on Environmental Health article reviewed formaldehyde exposure from treated uniforms. It reported uniforms with 26 to 83 ppm formaldehyde and linked perspiring in those uniforms with more skin symptoms.
That article is about uniforms, not sheets. The useful lesson for bedding is narrower: treated textiles can matter, especially with heat, friction, and sweat.
What to do
Choose plain linen or plain cotton. Look for GOTS organic cotton, European flax linen, or OEKO-TEX Standard 100 if available. Skip wrinkle-resistant and stain-resistant bedding. If you are changing bedding slowly, start with the pillowcase because it touches your face every night.
The research at a glance
| Study | Journal | Year |
|---|---|---|
| Unfinished business: formaldehyde exposure from uniforms and the case for U.S. textile regulation. | Rev Environ Health | 2025 |